It started as a blog about building a mini-ITX server running Linux. Since then I've posted more general articles about computer software, hardware and anything else related. (all spam comments will be removed)

Friday, 4 October 2013

OSX Time Machine kills old disks

Round 1

Earlier this year I decided to replace the disk in my Macbook Pro with an SSD. The HDD was only a year old but I was already having problems that required frequent fixing in DiskUtility. Also those odd clicking noises it was making were making me feel nervous.

I decided to backup asap (once I'd fixed the disk again) and set about manually copying my data to an external disk in the finder window. After is kept failing on a bad block I decided to try and update my Time Machine backup instead. It ran for a while and then the machine froze, forcing me to reboot the machine. I then found that the disk was corrupted and Diskutility could see it but refused to touch it.

I bought a copy of Stellar Phoenix Mac Recovery because the demo version showed all my files listed, but after recovering about 200Gb they all proved unusable. Other attempts have proved equally unsuccessful with days of processing not finding any files what-so-ever. My experience of buying recovery software has proven to be a huge waste of money! (I found similar trying to recover ReiserFS partitions)

THE FOLLOWING DISK SECTORS COULD NOT BE READ: 16585216, 16585217, 16585218, 16585219, 16585220, 16585221, 16585222, 16585223,

CANNOT READ: BLK 567944160

CONTINUE? [yn] y

THE FOLLOWING DISK SECTORS COULD NOT BE READ: 567944168, 567944169, 567944170, 567944171, 567944172, 567944173, 567944174, 567944175,

SEARCH FOR ALTERNATE SUPER-BLOCK FAILED. YOU MUST USE THE
-b OPTION TO FSCK TO SPECIFY THE LOCATION OF AN ALTERNATE
SUPER-BLOCK TO SUPPLY NEEDED INFORMATION; SEE fsck(8).

So that didn't work then! (I haven't got a clue where I'd find an alternative super-block.)

Round 2

This last weekend I bought a new USB portable disk unit to use as a new Time Machine volume. My wife's Macbook hadn't been backed up since earlier this year so I decided that was the first machine to try it out on.

I hooked up the drive, kicked off Time Machine and left it running. I noticed after about an hour that it was stuck at 48% so I attempted to kill it and start again, but the Macbook refused to respond. In the end I rebooted the machine but wasn't able to get past a blank grey startup screen. I booted from a startup CD can ran DiskUtility but it refused to see the internal disk.

In the end I replaced the HDD (which was 4½ years old) and recovered from her old Time Machine backup. So that's another internal disk that Time Machine pushed over the edge, and this time it refused to show as a drive.

I'm definitely reaching the conclusion that you shouldn't use Time Machine if you have any doubts over the integrity of your hard disk. Make sure you backup regularly and you'll not lose much.

You do backup don't you?

Update (10th Oct)

I've found that Disk Warrior 4.4 can cope with a faulty disk and will mount this disk in read-only mode so that you can copy off your files. It wasn't without it's problems though, the failing disk causing disk copies to occasionally hang on certain files.